package com.gzs.zhdj.interceptor;

import com.alibaba.fastjson.JSONObject;
import com.gzs.zhdj.constant.JwtClaimsConstant;
import com.gzs.zhdj.constant.MessageConstant;
import com.gzs.zhdj.context.BaseContext;
import com.gzs.zhdj.properties.JwtProperties;
import com.gzs.zhdj.utils.CommonResponse;
import com.gzs.zhdj.utils.JwtUtils;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * jwt令牌校验的拦截器
 */
@Component
@Slf4j
public class JwtTokenAdminInterceptor implements HandlerInterceptor {

    @Autowired
    private JwtProperties jwtProperties;

    /**
     * 校验jwt
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法，直接放行
            return true;
        }

        //1、从请求头中获取令牌
        String token = request.getHeader("Authorization");

        //2.判断令牌是否存在，如果不存在，返回错误结果（未登录）。
        if(!StringUtils.hasLength(token)){
            log.info("请求头token为空,返回未登录的信息");
            CommonResponse error = CommonResponse.fail(MessageConstant.USER_NOT_LOGIN);
            //手动转换 对象--json --------> 阿里巴巴fastJSON
            response.setCharacterEncoding("UTF-8");
            response.setContentType("application/json; charset=UTF-8");
            String notLogin = JSONObject.toJSONString(error);
            response.getWriter().write(notLogin);
            return false;
        }
        //3、校验令牌
        try {
            log.info("jwt校验:{}", token);
            Claims claims = JwtUtils.parseJWT(jwtProperties.getAdminSecretKey(), token);
            int id = Integer.parseInt(claims.get(JwtClaimsConstant.PartyMember_ID).toString());
            log.info("当前党员id：{}", id);
            BaseContext.setCurrentId(id);
            //4、通过，放行
            return true;
        } catch (Exception ex) {
            //4、不通过，响应401状态码
            log.info("解析令牌失败, 返回未登录错误信息");
            CommonResponse error = CommonResponse.fail(MessageConstant.USER_NOT_LOGIN);
            //手动转换 对象--json
            response.setCharacterEncoding("UTF-8");
            response.setContentType("application/json; charset=UTF-8");
            String notLogin = JSONObject.toJSONString(error);
            response.getWriter().write(notLogin);
            return false;
        }
    }
}
